| page.title=Creating a Search Interface |
| parent.title=Search |
| parent.link=index.html |
| @jd:body |
| |
| <div id="qv-wrapper"> |
| <div id="qv"> |
| |
| <h2>Quickview</h2> |
| <ul> |
| <li>The Android system sends search queries from the search dialog or widget to an activity you |
| specify to perform searches and present results</li> |
| <li>You can put the search widget in the Action Bar, as an "action view," for quick |
| access</li> |
| </ul> |
| |
| |
| <h2>In this document</h2> |
| <ol> |
| <li><a href="#TheBasics">The Basics</a></li> |
| <li><a href="#SearchableConfiguration">Creating a Searchable Configuration</a></li> |
| <li><a href="#SearchableActivity">Creating a Searchable Activity</a> |
| <ol> |
| <li><a href="#DeclaringSearchableActivity">Declaring a searchable activity</a></li> |
| <li><a href="#PerformingSearch">Performing a search</a></li> |
| </ol> |
| </li> |
| <li><a href="#SearchDialog">Using the Search Dialog</a> |
| <ol> |
| <li><a href="#InvokingTheSearchDialog">Invoking the search dialog</a></li> |
| <li><a href="#LifeCycle">The impact of the search dialog on your activity lifecycle</a></li> |
| <li><a href="#SearchContextData">Passing search context data</a></li> |
| </ol> |
| </li> |
| <li><a href="#UsingSearchWidget">Using the Search Widget</a> |
| <ol> |
| <li><a href="#ConfiguringWidget">Configuring the search widget</a></li> |
| <li><a href="#WidgetFeatures">Other search widget features</a></li> |
| <li><a href="#UsingBoth">Using both the widget and the dialog</a></li> |
| </ol> |
| </li> |
| <li><a href="#VoiceSearch">Adding Voice Search</a></li> |
| <li><a href="#SearchSuggestions">Adding Search Suggestions</a></li> |
| </ol> |
| |
| <h2>Key classes</h2> |
| <ol> |
| <li>{@link android.app.SearchManager}</li> |
| <li>{@link android.widget.SearchView}</li> |
| </ol> |
| |
| <h2>Related samples</h2> |
| <ol> |
| <li><a href="{@docRoot}resources/samples/SearchableDictionary/index.html">Searchable |
| Dictionary</a></li> |
| <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/SearchViewActionBar.html">SearchView |
| in the Action Bar</a></li> |
| <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/SearchViewFilterMode.html">SearchView |
| filter mode</a></li> |
| </ol> |
| |
| <h2>Downloads</h2> |
| <ol> |
| <li><a href="{@docRoot}shareables/search_icons.zip">search_icons.zip</a></li> |
| </ol> |
| |
| <h2>See also</h2> |
| <ol> |
| <li><a href="adding-recent-query-suggestions.html">Adding Recent Query Suggestions</a></li> |
| <li><a href="adding-custom-suggestions.html">Adding Custom Suggestions</a></li> |
| <li><a href="searchable-config.html">Searchable Configuration</a></li> |
| </ol> |
| |
| </div> |
| </div> |
| |
| <p>When you're ready to add search functionality to your application, Android helps you implement |
| the user interface with either a search dialog that appears at the top of the activity window or a |
| search widget that you can insert in your layout. Both the search dialog and the widget can deliver |
| the user's search query to a specific activity in your application. This way, the user can initiate |
| a search from any activity where the search dialog or widget is available, and the system starts the |
| appropriate activity to perform the search and present results.</p> |
| |
| <p>Other features available for the search dialog and widget include:</p> |
| |
| <ul> |
| <li>Voice search</li> |
| <li>Search suggestions based on recent queries</li> |
| <li>Search suggestions that match actual results in your application data</li> |
| </ul> |
| |
| <p>This guide shows you how to set up your application to provide a search interface |
| that's assisted by the Android system to deliver search queries, using either the |
| search dialog or the search widget.</p> |
| |
| |
| <h2 id="TheBasics">The Basics</h2> |
| |
| <div class="figure" style="width:250px"> |
| <img src="{@docRoot}images/search/search-ui.png" alt="" height="417" /> |
| <p class="img-caption"><strong>Figure 1.</strong> Screenshot of an application's search dialog.</p> |
| </div> |
| |
| <p>Before you begin, you should decide whether you'll implement your search interface using the |
| search dialog or the search widget. Both provide the same search features, but in slightly different |
| ways:</p> |
| |
| <ul> |
| <li>The <strong>search dialog</strong> is a UI component that's controlled by the Android system. |
| When activated by the user, the search dialog appears at the top of the activity, as shown in figure |
| 1. |
| <p>The Android system controls all events in the search dialog. When the user |
| submits a query, the system delivers the query to the activity that you specify to |
| handle searches. The dialog can also provide search suggestions while the user types.</p></li> |
| |
| <li>The <strong>search widget</strong> is an instance of {@link android.widget.SearchView} that |
| you can place anywhere in your layout. By default, the search widget behaves like a standard {@link |
| android.widget.EditText} widget and doesn't do anything, but you can configure it so that the |
| Android system handles all input events, delivers queries to the appropriate activity, and provides |
| search suggestions (just like the search dialog). However, the search widget is available only in |
| Android 3.0 (API Level 11) and higher. |
| |
| <p class="note"><strong>Note:</strong> If you want, you can handle all user input into the |
| search widget yourself, using various callback methods and listeners. This document, however, |
| focuses on how to integrate the search widget with the system for an assisted search |
| implementation. If you want to handle all user input yourself, read the reference documentation for |
| {@link android.widget.SearchView} and its nested interfaces. </p></li> |
| </ul> |
| |
| <p>When the user executes a search from the search dialog or a search widget, the system creates an |
| {@link android.content.Intent} and stores the user query in it. The system then starts the activity |
| that you've declared to handle searches (the "searchable activity") and delivers it the intent. To |
| set up your application for this kind of assisted search, you need the following:</p> |
| |
| <ul> |
| <li>A searchable configuration |
| <p>An XML file that configures some settings for the search dialog or widget. It includes settings |
| for features such as voice search, search suggestion, and hint text for the search box.</p></li> |
| <li>A searchable activity |
| <p>The {@link android.app.Activity} that receives the search query, searches your |
| data, and displays the search results.</p></li> |
| <li>A search interface, provided by either: |
| <ul> |
| <li>The search dialog |
| <p>By default, the search dialog is hidden, but appears at the top of the screen when the |
| user presses the device SEARCH button (when available) or another button in your user interface.</p> |
| </li> |
| <li>Or, a {@link android.widget.SearchView} widget |
| <p>Using the search widget allows you to put the search box anywhere in your activity. |
| Instead of putting it in your activity layout, however, it's usually more convenient for users as an |
| <a href="{@docRoot}guide/topics/ui/actionbar.html#ActionView">action view in the Action Bar</a>.</p> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| |
| <p>The rest of this document shows you how to create the searchable configuration, searchable |
| activity, and implement a search interface with either the search dialog or search widget.</p> |
| |
| |
| <h2 id="SearchableConfiguration">Creating a Searchable Configuration</h2> |
| |
| <p>The first thing you need is an XML file called the searchable configuration. It configures |
| certain UI aspects of the search dialog or widget and defines how features such as suggestions and |
| voice search behave. This file is traditionally named {@code searchable.xml} and must be saved in |
| the {@code res/xml/} project directory.</p> |
| |
| <p class="note"><strong>Note:</strong> The system uses this file to instantiate a {@link |
| android.app.SearchableInfo} object, but you cannot create this object yourself at |
| runtime—you must declare the searchable configuration in XML.</p> |
| |
| <p>The searchable configuration file must include the <a |
| href="{@docRoot}guide/topics/search/searchable-config.html#searchable-element">{@code |
| <searchable>}</a> element as the root node and specify one |
| or more attributes. For example:</p> |
| |
| <pre> |
| <?xml version="1.0" encoding="utf-8"?> |
| <searchable xmlns:android="http://schemas.android.com/apk/res/android" |
| android:label="@string/app_label" |
| android:hint="@string/search_hint" > |
| </searchable> |
| </pre> |
| |
| <p>The {@code android:label} attribute is the only required attribute. It points to a string |
| resource, which should be the application name. This label isn't actually visible to the |
| user until you enable search suggestions for Quick Search Box. At that point, this label is visible |
| in the list of Searchable items in the system Settings.</p> |
| |
| <p>Though it's not required, we recommend that you always include the {@code android:hint} |
| attribute, which provides a hint string in the search box before users |
| enters a query. The hint is important because it provides important clues to users about what |
| they can search.</p> |
| |
| <p class="note"><strong>Tip:</strong> For consistency among other |
| Android applications, you should format the string for {@code android:hint} as "Search |
| <content-or-product>". For example, "Search songs and artists" or "Search |
| YouTube".</p> |
| |
| <p>The <a |
| href="{@docRoot}guide/topics/search/searchable-config.html#searchable-element">{@code |
| <searchable>}</a> element accepts several other attributes. However, you don't need |
| most attributes until you add features such as <a href="#SearchSuggestions">search suggestions</a> |
| and <a href="#VoiceSearch">voice search</a>. For detailed information about the searchable |
| configuration file, see the <a |
| href="{@docRoot}guide/topics/search/searchable-config.html">Searchable Configuration</a> reference |
| document.</p> |
| |
| |
| |
| <h2 id="SearchableActivity">Creating a Searchable Activity</h2> |
| |
| <p>A searchable activity is the {@link android.app.Activity} in your application that performs |
| searches based on a query string and presents the search results.</p> |
| |
| <p>When the user executes a search in the search dialog or widget, the system starts your |
| searchable activity and delivers it the search query in an {@link |
| android.content.Intent} with the {@link android.content.Intent#ACTION_SEARCH} action. Your |
| searchable activity retrieves the query from the intent's {@link android.app.SearchManager#QUERY |
| QUERY} extra, then searches your data and presents the results.</p> |
| |
| <p>Because you may include the search dialog or widget in any other activity in your application, |
| the system must know which activity is your searchable activity, so it can properly deliver the |
| search query. So, you must first declare your searchable activity in the Android manifest file.</p> |
| |
| |
| <h3 id="DeclaringSearchableActivity">Declaring a searchable activity</h3> |
| |
| <p>If you don't have one already, create an {@link android.app.Activity} that will perform |
| searches and present results. You don't need to implement the search functionality yet—just |
| create an activity that you can declare in the manifest. Inside the manifest's <a |
| href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> |
| element:</p> |
| <ol> |
| <li>Declare the activity to accept the {@link android.content.Intent#ACTION_SEARCH} intent, in an |
| <a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">{@code |
| <intent-filter>}</a> |
| element.</li> |
| <li>Specify the searchable configuration to use, in a <a |
| href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| element.</li> |
| </ol> |
| |
| <p>For example:</p> |
| |
| <pre> |
| <application ... > |
| <activity android:name=".SearchableActivity" > |
| <intent-filter> |
| <action android:name="android.intent.action.SEARCH" /> |
| </intent-filter> |
| <meta-data android:name="android.app.searchable" |
| android:resource="@xml/searchable"/> |
| </activity> |
| ... |
| </application> |
| </pre> |
| |
| <p>The {@code <meta-data>} element must include the {@code android:name} attribute with a |
| value of {@code "android.app.searchable"} and the {@code android:resource} attribute with a |
| reference to the searchable configuration file (in this example, it |
| refers to the {@code res/xml/searchable.xml} file).</p> |
| |
| <p class="note"><strong>Note:</strong> The <a |
| href="{@docRoot}guide/topics/manifest/intent-filter-element.html">{@code |
| <intent-filter>}</a> does not need a <a |
| href="{@docRoot}guide/topics/manifest/category-element.html">{@code <category>}</a> with the |
| {@code DEFAULT} value (which you usually see in <a |
| href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> elements), |
| because the system delivers the {@link android.content.Intent#ACTION_SEARCH} intent explicitly to |
| your searchable activity, using its component name.</p> |
| |
| |
| |
| <h3 id="PerformingSearch">Performing a search</h3> |
| |
| <p>Once you have declared your searchable activity in the manifest, performing a search in your |
| searchable activity involves three steps:</p> |
| |
| <ol> |
| <li><a href="#ReceivingTheQuery">Receiving the query</a></li> |
| <li><a href="#SearchingYourData">Searching your data</a></li> |
| <li><a href="#PresentingTheResults">Presenting the results</a></li> |
| </ol> |
| |
| <p>Traditionally, your search results should be presented in a {@link android.widget.ListView}, so |
| you might want your searchable activity to extend {@link android.app.ListActivity}. It includes |
| a default layout with a single {@link android.widget.ListView} and provides several |
| convenience methods for working with the {@link android.widget.ListView}.</p> |
| |
| |
| <h4 id="ReceivingTheQuery">Receiving the query</h4> |
| |
| <p>When a user executes a search from the search dialog or widget, the system starts your |
| searchable activity and sends it a {@link android.content.Intent#ACTION_SEARCH} intent. This intent |
| carries the search query in the |
| {@link android.app.SearchManager#QUERY QUERY} string extra. You must check for |
| this intent when the activity starts and extract the string. For example, here's how you can get the |
| search query when your searchable activity starts:</p> |
| |
| <pre> |
| @Override |
| public void onCreate(Bundle savedInstanceState) { |
| super.onCreate(savedInstanceState); |
| setContentView(R.layout.search); |
| |
| // Get the intent, verify the action and get the query |
| Intent intent = getIntent(); |
| if (Intent.ACTION_SEARCH.equals(intent.getAction())) { |
| String query = intent.getStringExtra(SearchManager.QUERY); |
| doMySearch(query); |
| } |
| } |
| </pre> |
| |
| <p>The {@link android.app.SearchManager#QUERY QUERY} string is always included with |
| the {@link android.content.Intent#ACTION_SEARCH} intent. In this example, the query is |
| retrieved and passed to a local {@code doMySearch()} method where the actual search operation |
| is done.</p> |
| |
| |
| <h4 id="SearchingYourData">Searching your data</h4> |
| |
| <p>The process of storing and searching your data is unique to your application. |
| You can store and search your data in many ways, but this guide does not show you how to store your |
| data and search it. Storing and searching your data is something you should carefully consider in |
| terms of your needs and your data format. However, here are some tips you might be able to |
| apply:</p> |
| |
| <ul> |
| <li>If your data is stored in a SQLite database on the device, performing a full-text search |
| (using FTS3, rather than a {@code LIKE} query) can provide a more robust search across text data and |
| can produce results significantly faster. See <a href="http://sqlite.org/fts3.html">sqlite.org</a> |
| for information about FTS3 and the {@link android.database.sqlite.SQLiteDatabase} class for |
| information about SQLite on Android. Also look at the <a |
| href="{@docRoot}resources/samples/SearchableDictionary/index.html">Searchable Dictionary</a> sample |
| application to see a complete SQLite implementation that performs searches with FTS3.</li> |
| <li>If your data is stored online, then the perceived search performance might be |
| inhibited by the user's data connection. You might want to display a spinning progress wheel until |
| your search returns. See {@link android.net} for a reference of network APIs and <a |
| href="{@docRoot}guide/topics/ui/dialogs.html#ProgressDialog">Creating a Progress Dialog</a> |
| for information about how to display a progress wheel.</li> |
| </ul> |
| |
| |
| <div class="sidebox-wrapper"> |
| <div class="sidebox"> |
| <h2>About Adapters</h2> |
| <p>An {@link android.widget.Adapter} binds each item from a set of data into a |
| {@link android.view.View} object. When the {@link android.widget.Adapter} |
| is applied to a {@link android.widget.ListView}, each piece of data is inserted as an individual |
| view into the list. {@link |
| android.widget.Adapter} is just an interface, so implementations such as {@link |
| android.widget.CursorAdapter} (for binding data from a {@link android.database.Cursor}) are needed. |
| If none of the existing implementations work for your data, then you can implement your own from |
| {@link android.widget.BaseAdapter}. Install the SDK Samples package for API Level 4 to see the |
| original version of the Searchable Dictionary, which creates a custom adapter to read data from |
| a file.</p> |
| </div> |
| </div> |
| |
| <p>Regardless of where your data lives and how you search it, we recommend that you return search |
| results to your searchable activity with an {@link android.widget.Adapter}. This way, you can easily |
| present all the search results in a {@link android.widget.ListView}. If your data comes from a |
| SQLite database query, you can apply your results to a {@link android.widget.ListView} |
| using a {@link android.widget.CursorAdapter}. If your data comes in some other type of format, then |
| you can create an extension of {@link android.widget.BaseAdapter}.</p> |
| |
| |
| <h4 id="PresentingTheResults">Presenting the results</h4> |
| |
| <p>As discussed above, the recommended UI for your search results is a {@link |
| android.widget.ListView}, so you might want your searchable activity to extend {@link |
| android.app.ListActivity}. You can then call {@link |
| android.app.ListActivity#setListAdapter(ListAdapter) setListAdapter()}, passing it an {@link |
| android.widget.Adapter} that is bound to your data. This injects all the |
| search results into the activity {@link android.widget.ListView}.</p> |
| |
| <p>For more help presenting your results in a list, see the {@link android.app.ListActivity} |
| documentation.</p> |
| |
| <p>Also see the <a |
| href="{@docRoot}resources/samples/SearchableDictionary/index.html">Searchable Dictionary</a> sample |
| for an a complete demonstration of how to search an SQLite database and use an |
| {@link android.widget.Adapter} to provide results in a {@link android.widget.ListView}.</p> |
| |
| |
| |
| |
| |
| <h2 id="SearchDialog">Using the Search Dialog</h2> |
| |
| <div class="sidebox-wrapper"> |
| <div class="sidebox"> |
| <h2>Should I use the search dialog or the widget?</h2> |
| <p>The answer depends mostly on whether you are developing for Android 3.0 (API Level 11 or |
| higher), because the {@link android.widget.SearchView} widget was introduced in Android 3.0. So, |
| if you are developing your application for a version of Android lower than 3.0, the search widget is |
| not an option and you should use the search dialog to implement your search interface.</p> |
| <p>If you <em>are</em> developing for Android 3.0 or higher, then the decision depends more on |
| your needs. In most cases, we recommend that you use the search widget as an "action view" in the |
| Action Bar. However, it might not be an option for you to put the search |
| widget in the Action Bar for some reason (perhaps there's not enough space or you don't use the |
| Action Bar). So, you might instead want to put the search widget somewhere in your activity layout. |
| And if all else fails, you can still use the search dialog if you prefer to keep the search box |
| hidden. In fact, you might want to offer both the dialog and the widget in some cases. For more |
| information about the widget, skip to <a href="#UsingSearchWidget">Using the Search Widget</a>.</p> |
| </div> |
| </div> |
| |
| <p>The search dialog provides a floating search box at the top of the screen, with the application |
| icon on the left. The search dialog can provide search suggestions as the user types and, when |
| the user executes a search, the system sends the search query to a |
| searchable activity that performs the search. However, if you are developing |
| your application for devices running Android 3.0, you should consider using the search widget |
| instead (see the side box).</p> |
| |
| <p>The search dialog is always hidden by default, until the user activates it. If the user's device |
| includes a SEARCH button, pressing it will activate the search dialog by default. Your application |
| can also activate the search dialog on demand by calling {@link |
| android.app.Activity#onSearchRequested onSearchRequested()}. However, neither of these work |
| until you enable the search dialog for the activity.</p> |
| |
| <p>To enable the search dialog, you must indicate to the system which searchable activity should |
| receive search queries from the search dialog, in order to perform searches. For example, in the |
| previous section about <a href="#SearchableActivity">Creating a Searchable Activity</a>, a |
| searchable activity named {@code SearchableActivity} was created. If you want a separate activity, |
| named {@code OtherActivity}, to show the search dialog and deliver searches to {@code |
| SearchableActivity}, you must declare in the manifest that {@code SearchableActivity} is the |
| searchable activity to use for the search dialog in {@code OtherActivity}.</p> |
| |
| <p>To declare the searchable activity for an activity's search dialog, |
| add a <a href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| element inside the respective activity's <a |
| href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a> element. |
| The <a href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| element must include the {@code android:value} attribute that specifies the searchable activity's |
| class name and the {@code android:name} attribute with a value of {@code |
| "android.app.default_searchable"}.</p> |
| |
| <p>For example, here is the declaration for |
| both a searchable activity, {@code SearchableActivity}, and another activity, {@code |
| OtherActivity}, which uses {@code SearchableActivity} to perform searches executed from its |
| search dialog:</p> |
| |
| <pre> |
| <application ... > |
| <!-- this is the searchable activity; it performs searches --> |
| <activity android:name=".SearchableActivity" > |
| <intent-filter> |
| <action android:name="android.intent.action.SEARCH" /> |
| </intent-filter> |
| <meta-data android:name="android.app.searchable" |
| android:resource="@xml/searchable"/> |
| </activity> |
| |
| <!-- this activity enables the search dialog to initiate searches |
| in the SearchableActivity --> |
| <activity android:name=".OtherActivity" ... > |
| <!-- enable the search dialog to send searches to SearchableActivity --> |
| <b><meta-data android:name="android.app.default_searchable" |
| android:value=".SearchableActivity" /></b> |
| </activity> |
| ... |
| </application> |
| </pre> |
| |
| <p>Because the {@code OtherActivity} now includes a <a |
| href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| element to declare which searchable activity to use for searches, the activity has enabled the |
| search dialog. |
| While the user is in this activity, the device SEARCH button (if available) and the {@link |
| android.app.Activity#onSearchRequested onSearchRequested()} method will activate the search dialog. |
| When the user executes the search, the system starts {@code SearchableActivity} and delivers it |
| the {@link android.content.Intent#ACTION_SEARCH} intent.</p> |
| |
| <p class="note"><strong>Note:</strong> The searchable activity itself provides the search dialog |
| by default, so you don't need to add this declaration to {@code SearchableActivity}.</p> |
| |
| <p>If you want every activity in your application to provide the search dialog, insert the above <a |
| href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| element as a child of the <a |
| href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a> |
| element, instead of each <a |
| href="{@docRoot}guide/topics/manifest/activity-element.html">{@code <activity>}</a>. This |
| way, every activity inherits the value, provides the search dialog, and delivers searches to |
| the same searchable activity. (If you have multiple searchable activities, you can override the |
| default searchable activity by placing a different <a |
| href="{@docRoot}guide/topics/manifest/meta-data-element.html">{@code <meta-data>}</a> |
| declaration inside individual activities.)</p> |
| |
| <p>With the search dialog now enabled for your activities, your application is ready to perform |
| searches.</p> |
| |
| |
| <h3 id="InvokingTheSearchDialog">Invoking the search dialog</h3> |
| |
| <p>As mentioned above, the device SEARCH button will open the search dialog as long as the current |
| activity has declared in the manifest the searchable activity to use.</p> |
| |
| <p>However, some devices do not include a dedicated SEARCH button, so you should not assume that |
| it's always available. When using the search dialog, you must <strong>always provide another search |
| button in your UI</strong> that activates the search dialog by calling {@link |
| android.app.Activity#onSearchRequested()}.</p> |
| |
| <p>For instance, you should either provide a menu item in your <a |
| href="{@docRoot}guide/topics/ui/menus.html#options-menu">Options Menu</a> or a button in your |
| activity layout that |
| activates search by calling {@link android.app.Activity#onSearchRequested()}. The <a |
| href="{@docRoot}shareables/search_icons.zip">search_icons.zip</a> file includes icons for |
| medium and high density screens, which you can use for your search menu item or button (low-density |
| screens scale-down the hdpi image by one half). </p> |
| |
| <p>You can also enable "type-to-search" functionality, which activates the search dialog when the |
| user starts typing on the keyboard—the keystrokes are inserted into the search dialog. You can |
| enable type-to-search in your activity by calling |
| {@link android.app.Activity#setDefaultKeyMode(int) setDefaultKeyMode}({@link |
| android.app.Activity#DEFAULT_KEYS_SEARCH_LOCAL}) during your activity's |
| {@link android.app.Activity#onCreate(Bundle) onCreate()} method.</p> |
| |
| |
| <h3 id="LifeCycle">The impact of the search dialog on your activity lifecycle</h3> |
| |
| <p>The search dialog is a {@link android.app.Dialog} that floats at the top of the |
| screen. It does not cause any change in the activity stack, so when the search dialog appears, no |
| lifecycle methods (such as {@link android.app.Activity#onPause()}) are called. Your activity just |
| loses input focus, as input focus is given to the search dialog. |
| </p> |
| |
| <p>If you want to be notified when the search dialog is activated, override the {@link |
| android.app.Activity#onSearchRequested()} method. When the system calls this method, it is an |
| indication that your activity has lost input focus to the search dialog, so you can do any |
| work appropriate for the event (such as pause |
| a game). Unless you are <a |
| href="#SearchContextData">passing search context data</a> |
| (discussed below), you should end the method by calling the super class implementation. For |
| example:</p> |
| |
| <pre> |
| @Override |
| public boolean onSearchRequested() { |
| pauseSomeStuff(); |
| return super.onSearchRequested(); |
| } |
| </pre> |
| |
| <p>If the user cancels search by pressing the <em>Back</em> button, the search dialog closes and the |
| activity |
| regains input focus. You can register to be notified when the search dialog is |
| closed with {@link android.app.SearchManager#setOnDismissListener(SearchManager.OnDismissListener) |
| setOnDismissListener()} |
| and/or {@link android.app.SearchManager#setOnCancelListener(SearchManager.OnCancelListener) |
| setOnCancelListener()}. You |
| should need to register only the {@link android.app.SearchManager.OnDismissListener |
| OnDismissListener}, because it is called every time the search dialog closes. The {@link |
| android.app.SearchManager.OnCancelListener OnCancelListener} only pertains to events in which the |
| user explicitly exited the search dialog, so it is not called when a search is executed (in which |
| case, the search dialog naturally disappears).</p> |
| |
| <p>If the current activity is not the searchable activity, then the normal activity lifecycle |
| events are triggered once the user executes a search (the current activity receives {@link |
| android.app.Activity#onPause()} and so forth, as |
| described in the <a |
| href="{@docRoot}guide/topics/fundamentals/activities.html#Lifecycle">Activities</a> |
| document). If, however, the current activity is the searchable activity, then one of two |
| things happens:</p> |
| |
| <ol type="a"> |
| <li>By default, the searchable activity receives the {@link |
| android.content.Intent#ACTION_SEARCH} intent with a call to {@link |
| android.app.Activity#onCreate(Bundle) onCreate()} and a new instance of the |
| activity is brought to the top of the activity stack. There are now two instances of your |
| searchable activity in the activity stack (so pressing the <em>Back</em> button goes back to the |
| previous |
| instance of the searchable activity, rather than exiting the searchable activity).</li> |
| <li>If you set {@code android:launchMode} to <code>"singleTop"</code>, then the |
| searchable activity receives the {@link android.content.Intent#ACTION_SEARCH} intent with a call |
| to {@link android.app.Activity#onNewIntent(Intent)}, passing the new {@link |
| android.content.Intent#ACTION_SEARCH} intent here. For example, here's how you might handle |
| this case, in which the searchable activity's launch mode is <code>"singleTop"</code>: |
| <pre> |
| @Override |
| public void onCreate(Bundle savedInstanceState) { |
| super.onCreate(savedInstanceState); |
| setContentView(R.layout.search); |
| handleIntent(getIntent()); |
| } |
| |
| @Override |
| protected void onNewIntent(Intent intent) { |
| setIntent(intent); |
| handleIntent(intent); |
| } |
| |
| private void handleIntent(Intent intent) { |
| if (Intent.ACTION_SEARCH.equals(intent.getAction())) { |
| String query = intent.getStringExtra(SearchManager.QUERY); |
| doMySearch(query); |
| } |
| } |
| </pre> |
| |
| <p>Compared to the example code in the section about <a href="#PerformingSearch">Performing a |
| Search</a>, all the code to handle the |
| search intent is now in the {@code handleIntent()} method, so that both {@link |
| android.app.Activity#onCreate(Bundle) |
| onCreate()} and {@link android.app.Activity#onNewIntent(Intent) onNewIntent()} can execute it.</p> |
| |
| <p>When the system calls {@link android.app.Activity#onNewIntent(Intent)}, the activity has |
| not been restarted, so the {@link android.app.Activity#getIntent()} method |
| returns the same intent that was received with {@link |
| android.app.Activity#onCreate(Bundle) onCreate()}. This is why you should call {@link |
| android.app.Activity#setIntent(Intent)} inside {@link |
| android.app.Activity#onNewIntent(Intent)} (so that the intent saved by the activity is updated in |
| case you call {@link android.app.Activity#getIntent()} in the future).</p> |
| |
| </li> |
| </ol> |
| |
| <p>The second scenario using <code>"singleTop"</code> launch mode is usually ideal, because chances |
| are good that once a search is done, the user will perform additional searches and it's a bad |
| experience if your application creates multiple instances of the searchable activity. So, we |
| recommend that you set your searchable activity to <code>"singleTop"</code> launch mode in the |
| application manifest. For example:</p> |
| |
| <pre> |
| <activity android:name=".SearchableActivity" |
| <b>android:launchMode="singleTop"</b> > |
| <intent-filter> |
| <action android:name="android.intent.action.SEARCH" /> |
| </intent-filter> |
| <meta-data android:name="android.app.searchable" |
| android:resource="@xml/searchable"/> |
| </activity> |
| </pre> |
| |
| |
| |
| <h3 id="SearchContextData">Passing search context data</h3> |
| |
| <p>In some cases, you can make necessary refinements to the search query inside the searchable |
| activity, for every search made. However, if you want to refine your search criteria based on the |
| activity from which the user is performing a search, you can provide additional data in the intent |
| that the system sends to your searchable activity. You can pass the additional data in the {@link |
| android.app.SearchManager#APP_DATA} {@link android.os.Bundle}, which is included in the {@link |
| android.content.Intent#ACTION_SEARCH} intent.</p> |
| |
| <p>To pass this kind of data to your searchable activity, override the {@link |
| android.app.Activity#onSearchRequested()} method for the activity from which the user can perform a |
| search, create a {@link android.os.Bundle} with the additional data, and call {@link |
| android.app.Activity#startSearch startSearch()} to activate the search dialog. |
| For example:</p> |
| |
| <pre> |
| @Override |
| public boolean onSearchRequested() { |
| Bundle appData = new Bundle(); |
| appData.putBoolean(SearchableActivity.JARGON, true); |
| startSearch(null, false, appData, false); |
| return true; |
| } |
| </pre> |
| |
| <p>Returning "true" indicates that you have successfully handled this callback event and |
| called {@link android.app.Activity#startSearch startSearch()} to activate |
| the search dialog. Once the user submits a query, it's delivered to your |
| searchable activity along with the data you've added. You can extract the extra data from the {@link |
| android.app.SearchManager#APP_DATA} {@link android.os.Bundle} to refine the search. For example:</p> |
| |
| <pre> |
| Bundle appData = getIntent().getBundleExtra(SearchManager.APP_DATA); |
| if (appData != null) { |
| boolean jargon = appData.getBoolean(SearchableActivity.JARGON); |
| } |
| </pre> |
| |
| <p class="caution"><strong>Caution:</strong> Never call the {@link |
| android.app.Activity#startSearch(String,boolean,Bundle,boolean) startSearch()} method from outside |
| the {@link android.app.Activity#onSearchRequested()} callback method. To activate the search dialog |
| in your activity, always call {@link android.app.Activity#onSearchRequested()}. Otherwise, {@link |
| android.app.Activity#onSearchRequested()} is not called and customizations (such as the addition of |
| {@code appData} in the above example) are missed.</p> |
| |
| |
| |
| <h2 id="UsingSearchWidget">Using the Search Widget</h2> |
| |
| <div class="figure" style="width:429px;margin:0"> |
| <img src="{@docRoot}images/ui/actionbar-actionview.png" alt="" /> |
| <p class="img-caption"><strong>Figure 2.</strong> The {@link |
| android.widget.SearchView} widget as an "action view" in the Action Bar.</p> |
| </div> |
| |
| <p>The {@link android.widget.SearchView} widget is available in Android 3.0 and higher. If |
| you're developing your application for Android 3.0 and have decided to use the search widget, we |
| recommend that you insert the search widget as an <a |
| href="{@docRoot}guide/topics/ui/actionbar.html#ActionView">action view in the Action Bar</a>, |
| instead of using the search dialog (and instead of placing the search widget in your activity |
| layout). For example, figure 2 shows the search widget in the Action Bar.</p> |
| |
| <p>The search widget provides the same functionality as the search dialog. It starts the appropriate |
| activity when the user executes a search, and it can provide search suggestions and perform voice |
| search.</p> |
| |
| <p class="note"><strong>Note:</strong> When you use the search widget as an action view, you |
| still might need to support using the search dialog, for cases in which the search widget does |
| not fit in the Action Bar. See the following section about <a href="#UsingBoth">Using both |
| the widget and the dialog</a>.</p> |
| |
| |
| <h3 id="ConfiguringWidget">Configuring the search widget</h3> |
| |
| <p>After you've created a <a href="#SearchableConfiguration">searchable configuration</a> and a <a |
| href="#SearchableActivity">searchable activity</a>, as discussed above, you need to enable assisted |
| search for each {@link android.widget.SearchView}. You can do so by calling {@link |
| android.widget.SearchView#setSearchableInfo setSearchableInfo()} and passing it the {@link |
| android.app.SearchableInfo} object that represents your searchable configuration.</p> |
| |
| <p>You can get a reference to the {@link android.app.SearchableInfo} by calling {@link |
| android.app.SearchManager#getSearchableInfo getSearchableInfo()} on {@link |
| android.app.SearchManager}.</p> |
| |
| <p>For example, if you're using a {@link android.widget.SearchView} as an action view in the <a |
| href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a>, you should enable the widget |
| during the {@link android.app.Activity#onCreateOptionsMenu onCreateOptionsMenu()} callback:</p> |
| |
| <pre> |
| @Override |
| public boolean onCreateOptionsMenu(Menu menu) { |
| // Inflate the options menu from XML |
| MenuInflater inflater = getMenuInflater(); |
| inflater.inflate(R.menu.options_menu, menu); |
| |
| // Get the SearchView and set the searchable configuration |
| SearchManager searchManager = (SearchManager) {@link android.app.Activity#getSystemService getSystemService}(Context.SEARCH_SERVICE); |
| SearchView searchView = (SearchView) menu.findItem(R.id.menu_search).getActionView(); |
| searchView.setSearchableInfo(searchManager.getSearchableInfo({@link android.app.Activity#getComponentName()})); |
| searchView.setIconifiedByDefault(false); // Do not iconify the widget; expand it by default |
| |
| return true; |
| } |
| </pre> |
| |
| <p>That's all you need. The search widget is now configured and the system will deliver search |
| queries to your searchable activity. You can also enable <a href="#SearchSuggestions">search |
| suggestions</a> for the search widget.</p> |
| |
| <p class="note"><strong>Note:</strong> If you want to handle all user input yourself, you can do so |
| with some callback methods and event listeners. For more information, see the reference |
| documentation for {@link android.widget.SearchView} and its nested interfaces for the |
| appropriate event listeners.</p> |
| |
| <p>For more information about action views in the Action Bar, read the <a |
| href="{@docRoot}guide/topics/ui/actionbar.html#ActionView">Action Bar</a> developer guide (which |
| includes sample code for adding a search widget as an action view).</p> |
| |
| |
| <h3 id="WidgetFeatures">Other search widget features</h3> |
| |
| <p>The {@link android.widget.SearchView} widget allows for a few additional features you might |
| want:</p> |
| |
| <dl> |
| <dt>A submit button</dt> |
| <dd>By default, there's no button to submit a search query, so the user must press the |
| "Return" key on the keyboard to initiate a search. You can add a "submit" button by calling |
| {@link android.widget.SearchView#setSubmitButtonEnabled setSubmitButtonEnabled(true)}.</dd> |
| <dt>Query refinement for search suggestions</dt> |
| <dd>When you've enabled search suggestions, you usually expect users to simply select a |
| suggestion, but they might also want to refine the suggested search query. You can add a button |
| alongside each suggestion that inserts the suggestion in the search box for refinement by the |
| user, by calling {@link android.widget.SearchView#setQueryRefinementEnabled |
| setQueryRefinementEnabled(true)}.</dd> |
| <dt>The ability to toggle the search box visibility</dt> |
| <dd>By default, the search widget is "iconified," meaning that it is represented only by a |
| search icon (a magnifying glass), and expands to show the search box when the user touches it. |
| As shown above, you can show the search box by default, by calling {@link |
| android.widget.SearchView#setIconifiedByDefault setIconifiedByDefault(false)}. You can also |
| toggle the search widget appearance by calling {@link android.widget.SearchView#setIconified |
| setIconified()}.</dd> |
| </dl> |
| |
| <p>There are several other APIs in the {@link android.widget.SearchView} class that allow you to |
| customize the search widget. However, most of them are used only when you handle all |
| user input yourself, instead of using the Android system to deliver search queries and display |
| search suggestions.</p> |
| |
| |
| <h3 id="UsingBoth">Using both the widget and the dialog</h3> |
| |
| <p>If you insert the search widget in the Action Bar as an <a |
| href="{@docRoot}guide/topics/ui/actionbar.html#ActionView">action view</a>, and you enable it to |
| appear in the Action Bar "if there is room" (by setting {@code |
| android:showAsAction="ifRoom"}), then there is a chance that the search widget will not appear |
| as an action view, but the menu item will appear in the overflow menu. For example, when your |
| application runs on a smaller screen, there might not be enough room in the Action Bar to display |
| the search widget along with other action items or navigation elements, so the menu item will |
| instead appear in the overflow menu. When placed in the overflow menu, the item works like an |
| ordinary menu item and does not display the action view (the search widget).</p> |
| |
| <p>To handle this situation, the menu item to which you've attached the search widget should |
| activate the search dialog when the user selects it from the overflow menu. In order for it to do |
| so, you must implement {@link android.app.Activity#onOptionsItemSelected onOptionsItemSelected()} to |
| handle the "Search" menu item and open the search dialog by calling {@link |
| android.app.Activity#onSearchRequested onSearchRequested()}.</p> |
| |
| <p>For more information about how items in the Action Bar work and how to handle this situation, see |
| the <a href="{@docRoot}guide/topics/ui/actionbar.html">Action |
| Bar</a> developer guide.</p> |
| |
| <p>Also see the <a |
| href="{@docRoot}resources/samples/SearchableDictionary/src/com/example/android/searchabledict/SearchableDictionary.html" |
| >Searchable Dictionary</a> for an example implementation using |
| both the dialog and the widget.</p> |
| |
| |
| |
| <h2 id="VoiceSearch">Adding Voice Search</h2> |
| |
| <p>You can add voice search functionality to your search dialog or widget by adding the {@code |
| android:voiceSearchMode} attribute to your searchable configuration. This adds a voice search |
| button that launches a voice prompt. When the user |
| has finished speaking, the transcribed search query is sent to your searchable |
| activity.</p> |
| |
| <p>For example:</p> |
| |
| <pre> |
| <?xml version="1.0" encoding="utf-8"?> |
| <searchable xmlns:android="http://schemas.android.com/apk/res/android" |
| android:label="@string/search_label" |
| android:hint="@string/search_hint" |
| <b>android:voiceSearchMode="showVoiceSearchButton|launchRecognizer"</b> > |
| </searchable> |
| </pre> |
| |
| <p>The value {@code showVoiceSearchButton} is required to enable voice |
| search, while the second value, {@code launchRecognizer}, specifies that the voice search button |
| should launch a recognizer that returns the transcribed text to the searchable activity.</p> |
| |
| <p>You can provide additional attributes to specify the voice search behavior, such |
| as the language to be expected and the maximum number of results to return. See the <a |
| href="searchable-config.html">Searchable Configuration</a> reference for more information about the |
| available attributes.</p> |
| |
| <p class="note"><strong>Note:</strong> Carefully consider whether voice search is appropriate for |
| your application. All searches performed with the voice search button are immediately sent to |
| your searchable activity without a chance for the user to review the transcribed query. Sufficiently |
| test the voice recognition and ensure that it understands the types of queries that |
| the user might submit inside your application.</p> |
| |
| |
| |
| <h2 id="SearchSuggestions">Adding Search Suggestions</h2> |
| |
| <div class="figure" style="width:250px;margin:0"> |
| <img src="{@docRoot}images/search/search-suggest-custom.png" alt="" height="417" /> |
| <p class="img-caption"><strong>Figure 3.</strong> Screenshot of a search dialog with custom |
| search suggestions.</p> |
| </div> |
| |
| <p>Both the search dialog and the search widget can provide search suggestions as the user |
| types, with assistance from the Android system. The system manages the list of suggestions and |
| handles the event when the user selects a suggestion.</p> |
| |
| <p>You can provide two kinds of search suggestions:</p> |
| |
| <dl> |
| <dt>Recent query search suggestions</dt> |
| <dd>These suggestions are simply words that the user previously used as search queries in |
| your application. |
| <p>See <a href="adding-recent-query-suggestions.html">Adding Recent Query |
| Suggestions</a>.</p></dd> |
| <dt>Custom search suggestions</dt> |
| <dd>These are search suggestions that you provide from your own data source, to help users |
| immediately select the correct spelling or item they are searching for. Figure 3 shows an |
| example of custom suggestions for a dictionary application—the user can select a suggestion |
| to instantly go to the definition. |
| <p>See <a href="adding-custom-suggestions.html">Adding Custom |
| Suggestions</a></p></dd> |
| </dl> |
| |